The present invention relates to ventilation assemblies, such as window or door ventilation assemblies.
A known ventilation assembly comprises a passageway having two ends, one said end being locatable for communication with an interior space, the other said end being locatable for communication with a further space exterior to the interior space for passively permitting ventilation between the interior and exterior spaces.
In some locations, such as housing near motorways or airports or in city centres, such as on Brownfield sites, the noise exterior to a building, such as from aircraft or vehicles, may be relatively loud. Therefore, double glazing or secondary glazing systems have been developed for minimising the effects of such noise inside buildings. However, it is a requirement under building regulations for some interior spaces or rooms to be ventilated and, for this purpose, it is known to provide a ventilation slot through a head section of a window frame. However, a problem is that noise can travel from the exterior atmosphere through the ventilation slot, into the interior space or room concerned, thereby, to a certain extent defeating the purpose of noise attenuation features employed, such as double glazing or other forms of multiple glazing. It is known to provide what is known as an acoustic ventilator which incorporates foam defining a tortuous path through the ventilator. To be effective, such ventilators have to be large and bulky in construction, and they are very expensive. Some persons claim that small slotvents or canopies have acoustic attenuation properties, but it has been pointed out in xe2x80x9cA Sound Decisionxe2x80x9d, pages 31 to 32, Housing Association and Building Maintenance, October 1998 that such devices may be no more effective than their standard slot ventilators/canopy counterparts and that an effective acoustic vent will be physically large with a substantial mass of acoustic foam.
It is known to use an anti-sound system in an aircraft headset and to use an anti-sound system in a motorised/powered ventilation duct in order to counteract the constant noise of the fan motor.
The present invention aims to alleviate the problems of the prior art, and especially in relation to passive ventilation devices or assemblies which do not by virtue of their design and method of operation need a motor.
According to a first aspect of the present invention there is provided a ventilation assembly comprising a ventilation passageway having two ends, one said end being locatable for communication with an interior space, the other said end being locatable for communication with a further space exterior to the interior space for passively permitting ventilation between the interior and exterior spaces, and an anti-sound system for reducing the level, at a location in the interior space, of noise incident upon the passageway in the exterior space.
The ventilation assembly may comprise a wall vent.
Alternatively, the ventilation assembly may comprise a chimney.
The ventilation assembly may alternatively comprise a stack vent ventilation system, for example, a system incorporating a generally vertically extending duct for ventilating rooms through apertures at different heights.
According to a further aspect of the present invention there is provided a window or door ventilation assembly having a ventilation passageway extending from one side of the assembly to another side thereof, and an anti-sound system for reducing the level, at a location on one side of the assembly, of noise incident upon the passageway on the other side of the assembly.
The window or door ventilation assembly may comprise a glazed-in vent in which the passageway is defined by an elongate structure having an elongate body having a channel adapted to be positioned on an edge of a flat panel, e.g. a window pane, with the glazed-in vent being located between the edge of the panel and a frame surrounding the panel.
The window or door ventilation assembly may alternatively comprise a slotvent (or slot ventilator) system which includes a slotvent which is adapted to be mounted at an elongate ventilation slot formed through a section, e.g. a head section, of a window sash or window or door frame and preferably defining at least part of the passageway. The slotvent system may include a weather canopy located on one side of the section which is opposite a side thereof on which the slotvent is mounted.
Alternatively, the window or door ventilation assembly may comprise an elongate vent structure having a duct therethrough defining the passageway, the vent structure being adapted to be located between a peripheral edge of a window or door frame, e.g. the peripheral upper edge of a window frame head section, and a layer of building material spaced from the peripheral edge of the frame.
The window or door ventilation assembly is preferably adapted for location in the region of a window or door with one side thereof and one end of the passageway communicating with an interior space and the other side thereof and another end of the passageway communicating with a further space exterior to the interior space.
A further aspect of the invention provides a ventilated window or door ventilation assembly having a window or door and a window or door ventilation assembly as in the previous aspect of the invention mounted thereon for providing ventilation in the region of the window or door.
A number of preferred features for each aforesaid aspect of the invention will now be described.
Preferably, the interior space comprises a room, e.g. of a building. Preferably, the exterior space comprises the earth""s atmosphere.
Preferably, the anti-sound system includes a sound generator, preferably for counteracting, reducing, cancelling and/or attenuating noise. The sound generator may generate sound in phase opposition, e.g. 180xc2x0 out of phase with, noise.
A plurality of said sound generators may be employed in the anti-sound system.
A said sound generator may be electromagnetic.
A said sound generator may be piezoelectric.
A said sound generator may be electrostatic.
The anti-sound system may include at least one electromagnetic sound generator, as well as either a piezoelectric or electrostatic sound generator or both. An electromagnetic sound generator may be adapted to produce sounds of relatively low frequency and a said electrostatic or piezoelectric sound generator may be adapted to produce sounds of relatively high frequency. The electromagnetic sound generator may have a frequency range lower limit lower than and/or a frequency range upper limit lower than respective lower and upper frequency range limits of the electrostatic or piezoelectric sound generator.
At least one said sound generator may be located in the passageway.
At least one said sound generator may be located to the exterior of the passageway in the exterior space.
At least one said sound generator may be located in the interior space.
The assembly may include a background sound generator for generating sounds in addition to or as an alternative to sounds produced for cancelling, reducing, counteracting and/or attenuating noise. The background sound generator may include a memory device adapted to store background sounds. A selection device may be provided for selecting one or more of a selection of background sounds stored in the memory device. The selection device may comprise a button or other user-operable input device for configuring the background sound generator between an off configuration and one or more background sound selection configurations. The input device may also be adapted for selection of the anti-sound system between on and off configurations thereof.
A said background sound may comprise a simulation of a natural sound, such as that of a stream, weather, such as rain or thunder, the seashore or an underwater environment. A said selected background sound may comprise the sound of at least one animal, such as a bird, mammal or waterborne animal.
A said background sound may comprise music.
An advantage of an assembly including such a background sound generator is that not only may unwanted noise be addressed, but pleasant noises may be generated, such as for the purposes of relaxation, for example, in homes or work places.
Preferably, the anti-sound system includes a noise sensor for sensing noise. A plurality of said noise sensors may be provided.
At least one said noise sensor may be located to the exterior of the passageway, for example, in the earth""s atmosphere.
At least one said noise sensor may be located in the passageway of the assembly.
At least one said noise sensor may be located to the interior of the passageway, for example, in a room ventilated by the passageway.
The anti-sound system may include at least one error correction sound sensor. A said error correction sound sensor may be located in the passageway. A said error correction sound sensor may be located in a room ventilated by the passageway.
The anti-sound system preferably includes a control system which is adapted to receive signals from each said noise sensor and to control each said sound generator in response thereto. Where an error correction sound sensor is provided, the control system is preferably adapted to receive error correction signals from the error correction sound sensor and to control the output of at least one said sound generator in response thereto.
The control system may be located in the passageway and may comprise a control box.
The anti-sound system may include a power supply for powering the anti-sound system.
The power supply may include a battery and/or a mains supply, e.g. via a transformer, and/or a solar cell.
In a case where the assembly comprises a window or door ventilation assembly, the assembly may include a weather canopy for minimising the ingress of precipitation, such as rain, into a ventilation slot defining at least part of the passageway. The control system may comprise at least one box, preferably a waterproof/sealed box, located inside the canopy. At least one said noise sensor may be located on or inside the canopy. At least one said sound generator may be located on or inside said canopy. The assembly may include a ventilation control device, such as a slotvent or moveable flap, on a side thereof which is adapted to be located inside a room, with the weather canopy located to the exterior of the room. At least one said error correction noise sensor may be located in or on the canopy and/or in or on the ventilation control device and/or in a room ventilated by the assembly.
The canopy may comprise an elongate body, formed, for example, by extrusion, and may incorporate at least one solar cell located on the canopy. An outer surface of the canopy which extends substantially the length of the ventilation assembly may be substantially covered with one or more said solar cells.